A strategy for Scottish invertebrate conservationEnsuring important habitats, sites and endangered species are conserved

PREPARED BY THE INITIATIVE FOR SCOTTISH INVERTEBRATES

ISIInitiative for

Scottish Invertebrates

�

On 20th February 1991, the Edinburgh Entomological

Club established the Initiative for Scottish Insects (ISI)

to further knowledge and conservation of the Scottish

insect fauna. The ISI has since expanded to include all

invertebrates. Today, the ISI acts as a forum on

Scottish invertebrates and, through the expertise

available to the ISI, is an authoritative voice on their

status and ecology.

This strategy to conserve Scottish invertebrates is the

work of the ISI in consultation with relevant statutory

bodies, non-governmental organisations (NGOs) and

individual specialists. It represents the views of over

100 experts across a wide range of invertebrate

groups and related interests. The work to produce this

strategy was grant aided by Scottish Natural Heritage

(SNH) and co-ordinated by Buglife – The Invertebrate

Conservation Trust.

This document was published by Buglife – The Invertebrate

Conservation Trust with financial assistance from Butterfly

Conservation (Scotland), Bumblebee Conservation Trust, Forestry

Commission Scotland, RSPB Scotland, Scottish Wildlife Trust, SEPA

and The John Muir Trust.

Acknowledgements

Many people have been involved in the development of this

strategy. The ISI would particularly like to thank the following for

their help and support: Dave Goulson, Geoff Hancock,

Paul Kirkland, Craig Macadam, Iain MacGowan, Margaret Palmer,

Jamie Roberts, Graham Rotheray, Ro Scott, Matt Shardlow,

Mark Shaw, Alastair Sommerville, Ian Strachan, Alan Stubbs,

Chris Sydes, Athayde Tonhasca, Mark Young.

Citation: Macadam, C.R. and Rotheray, G.E. (eds.) 2009.

A strategy for Scottish invertebrate conservation.

Prepared by the Initiative for Scottish Invertebrates.

Published by Buglife – The Invertebrate Conservation Trust, Stirling.

ISBN: 978-1-904878-94-0 © January 2009

A strategy for Scottish invertebrate conservationPREPARED BY THE INITIATIVE FOR SCOTTISH INVERTEBRATES

Edited by Craig Macadam and Graham Rotheray.

With assistance from Geoff Hancock, Iain MacGowan

and Alastair Sommerville.

For more information contact:

Initiative for Scottish Invertebrates

c/o Buglife Scotland

Balallan House, 24 Allan Park

Stirling FK8 2QG.

Tel: 01786 446504

Email: craig.macadam@buglife.org.uk

Contents

Summary 3

Our Vision 4

Scope 4

Why Scottish invertebrates need conservation 5

Strategic objectives for conserving Scottish invertebrates 6

Habitats 6

Species 8

Mobilising support for the Strategy 10

Appendix 1 Why invertebrates are important for the environment 11

Appendix 2 Why invertebrates are important for the economy 13

Appendix 3 Current threats and risks to Scottish invertebrates 14

Appendix 4 Scottish Biodiversity List species and UKBAP Priority Species that occur in Scotland 18

Appendix 5 Internationally protected species that occur in Scotland 18

Appendix 6 Species known from Scotland that are protected by the Wildlife and Countryside Act 1981 19

Design: Redpoll DesignC Printed on recycled paper© Background photograph on front cover Ian Cameron - www.transientlight.co.uk. Species images, L To R, Nigel Jones, Bastiaan Wakkie, Calum Duncan/Marine Conservation Society, Paul Baker, Paul Kirkland/Butterfly Conservation Scotland.

�A strategy for Scottish invertebrate conservation

1. In consultation with a wide range of organisations and individuals, this strategy to conserve

Scottish invertebrates has been prepared by the Initiative for Scottish Invertebrates (ISI).

2. Scottish invertebrates, i.e. animals without backbones - from ants to worms, butterflies to

whelks, centipedes to sea urchins - are vital to the environment and to the economy. Their roles

in ecological services like pollination, waste disposal and recycling are irreplaceable. They are a

source of direct and indirect food for a wide range of wildlife and also people.

3. Over 1,400 Scottish invertebrate species are significant to UK biodiversity because they are

confined to Scotland. Many others have populations centred in Scotland. Scotland has the best

representation of upland species in the UK and is a refuge for species becoming rare or extinct

elsewhere in the UK and Europe.

4. Across Europe, including the UK, invertebrate biodiversity is declining and only a few

species are being actively conserved. Expert opinion is that an increasing number of Scottish

invertebrates are, or soon could be, critically endangered.

5. Major threats to Scottish invertebrates include habitat loss and fragmentation, climate

change, development pressures, competition from non-native species and pollution.

Lack of understanding is also an important issue.

6. This strategy will identify which are the most endangered species and which are the most

important habitats and sites. Conservation action can, in many cases, manage these threats and

reverse declines. Implementation of this strategy will deliver conservation plans for endangered

species and management plans for important habitats and sites.

7. By bringing together statutory agencies, non-governmental organisations (NGOs), local

communities and individuals across Scotland, this strategy will aim to build capacity and

create an impetus for effective invertebrate conservation action. The end result will be that

invertebrates are valued and conserved for their key roles and that a wide range of people and

organisations will be working in partnership to better use, understand and appreciate

the natural world.

8. Progress with the strategy will be reported annually by the means of a website which will

also provide news on new projects and report results of key actions as they are progressed.

Summary

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Our VisionOur vision is for a Scotland in

which invertebrates are valued and

conserved for their key roles in a

healthy environment and for their

potential to bring people together

to better use, understand and

appreciate the natural world.

We will achieve this through:

l mobilising expertise and data to

ensure important habitats, sites and

endangered species are recognised

and conserved;

l highlighting through publicity and

education the importance of Scottish

invertebrates and the conservation

issues they face.

Invertebrates are extremely diverse and include

creatures like sponges, worms, shellfish, slugs, snails,

crabs, lobsters, millipedes, mites, spiders and insects.

This conservation strategy covers these and other

invertebrates living on the Scottish mainland and

off-shore islands, including their freshwaters, and in

the seas around Scottish coasts.

l This is only the beginning of the process of conserving

Scottish invertebrates. This strategy will develop

methods, build capacity, harness experience and create

an impetus for effective conservation action for Scottish

invertebrates.

l The strategy works within existing legislative

frameworks and conservation initiatives; in particular,

the EU Habitats Directive, the European Invertebrate

Strategy, the UK Biodiversity Action Plan, the Scottish

Biodiversity Strategy and the SNH Species Action

Framework.

l The strategy complements and adds value to

invertebrate conservation work undertaken by statutory

bodies and NGOs.

l Key actions will be implemented through partnerships

established between the ISI and statutory agencies,

NGOs, landowners and managers, and interested

specialists.

Scope

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�A strategy for Scottish invertebrate conservation

Biodiversity importance

At least �4,000 invertebrate species exist in Scotland. This

is more than 1� times the number of all UK bird, mammal

and vascular plant species put together. Five terrestrial

invertebrate species and many more marine invertebrates

are unique to Scotland in the entire world. More than 1,400

are special in being confined to Scotland in the UK. Many

others have their UK populations centred in Scotland. More

montane and boreal (north European) species exist in

Scotland than elsewhere in the UK. Scotland is also the last

stronghold for increasing numbers of invertebrate species

that have become rare or extinct elsewhere1,�. Despite

their significance, the conservation needs of most of these

species are poorly understood.

Over and above these species, unique variants and local

adaptations characterise many populations of Scottish

invertebrates. They represent an important fund of

biological diversity. This diversity arose in response to the

particular conditions in Scotland and is hugely significant

to UK and European biodiversity as a source of future

adaptability�.

Ecosystem services

Invertebrates are essential to the maintenance of healthy

ecosystem functioning. They provide vital services

including waste recycling and pollination, and form

the basis of most food chains. They are the “oil in the

ecological engine”. Without invertebrates, vertebrate and

plant life could not continue (Appendix 1).

Economic impact

Invertebrates underpin many important resources. Major

parts of Scotland’s rural and maritime economy depend

directly or indirectly on invertebrates (Appendix �).

Lack of action

Only a handful of invertebrate species are currently

benefiting from active conservation management.

Many habitats and sites in Scotland are protected as

Sites of Special Scientific Interest or as Special Areas of

Conservation however the invertebrate interest on these

sites is often overlooked. Protection of individual species

is possible through the legislation such as the Wildlife

and Countryside Act 1981, however only 19 Scottish

invertebrate species have such protection under European

and UK law (Appendices � and 6). Legal protection is

appropriate in some circumstances, however a far better

solution for invertebrate conservation is the appropriate

management of habitats and sites to benefit a wide range

of invertebrates.

Increasing threats

In common with invertebrates across Europe, many

Scottish species are declining. Major threats to Scottish

invertebrates include habitat loss and fragmentation,

climate change, development pressures, widespread use

of agrichemicals in modern farming and competition from

non-native species. Neglect and lack of understanding are

also important issues (Appendix �). Conservation action

can, in many cases, manage these threats and reverse

declines.

Why Scottish invertebrates need conservation

1 Rotheray, G.E. 1996. Why conserve Scottish insects? In Rotheray, G.E. and MacGowan, I. (Eds.) Conserving Scottish Insects, Edinburgh.� Young, M.R. and Rotheray, G.E. 1997. Insect Biodiversity in Scotland. In Fleming, L.V., Newton, A.C., Vickery, J.A. and Usher, M.B. (Eds.) Biodiversity in Scotland: Status, Trends and Initiatives. The Stationery Office, Edinburgh.

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Strategic objectives for conserving Scottish invertebrates

The following strategic objectives are divided into three

sections covering habitats, species and the mobilisation

of data and support. Successful implementation of

the strategy will require a partnership approach with the

involvement of all stakeholders. An implementation plan

will be developed, which will initially cover the period �009

to �01�. This plan will list the actions and projects required

to achieve the objectives and will ensure that progress is

made on all objectives. It will be a dynamic web-based

document and will be subject to regular review by the

Initiative for Scottish Invertebrates and updated as key

actions are progressed.

The mechanism for monitoring and review of the

strategy is as follows:

a) regular reports at Strategy Implementation Group

meetings

b) reports collated into annual web report

c) annual reports collated into two-yearly review with

recommendations.

Habitats

Habitats such as woodland, scrubland, grassland,

moorland, mountains, freshwater bodies, rivers, estuaries,

tubeworm reefs, gaping file shell beds and less obvious

wildlife habitats like agricultural set-aside, road verges,

post-industrial land, parks and gardens are all important for

Scottish invertebrates. To ensure that environmental and

economic benefits due to invertebrates continue, beneficial

management for invertebrates needs to be practised. At

present few habitats are suitably managed. This is because

invertebrates are either poorly appreciated or taken for

granted. Alternatively landowners and managers may be

willing to act, but lack the knowledge of what to do.

Furthermore, certain habitats and sites are more important

than others for invertebrates. Some of these are boreal

pine, birch, aspen and Atlantic oak woodlands, unimproved

grassland, the extensive bog systems of the Caithness and

Sutherland flows, many riverine habitats, coastal reefs,

certain mountains like the Cairngorms Plateau, glens like

Affric and Cannich and localities like Rannoch, the Solway

coast and Strathspey. In the deep waters to the east of

Mingulay in the Western Isles, there are cold water reefs

with exceptionally rich associated marine invertebrate

communities. Many more exist but are poorly recognised.

This is because their invertebrates are neglected in

assessments, accorded a low priority or they have not been

adequately surveyed.

The Marsh fritillary butterfly (Euphydryas aurinia) is

declining over most of Europe and is now extinct in

the Netherlands and Belgium. The UK is one of the

major European strongholds for the species, but even

here its range has contracted by over 60%. Argyll now

probably represents the most important area in the UK

for this species.

Some sites in Scotland have been lost through

agricultural intensification (e.g. drainage, heavy grazing)

or afforestation, while others have suffered from

under-grazing and even abandonment. The isolation of

many of the remaining colonies is a long-term threat to

their viability.

Beneficial habitat management, usually in the form of

low-intensity cattle grazing, is in place in many areas,

but this will depend in the long term on the economics

and availability of agri-environment schemes. There

are now five Special Areas of Conservation (SAC) which

have the Marsh Fritillary as a qualifying feature. Work

is continuing to develop and implement suitable

management regimes for these sites.

CASE STUDY

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OBJECTIVE 1

Produce and maintain a list of Scottish invertebrate habitats and sites. Based on a collation and analysis of species records,

Scottish habitats and sites will be assessed in terms

of their importance for invertebrates. Significant

invertebrate features will be highlighted and threats to

these habitats listed. Indicator groups and species, and

gaps in our knowledge, will be identified.

OBJECTIVE �

Devise and carry out a programme of assessment of prioritised invertebrate habitats and sites.To deal with gaps in knowledge, such as inadequate

survey and poor recognition and definition of important

invertebrate habitats and sites, a programme of

targeted assessments will be undertaken to provide the

missing data.

OBJECTIVE �

Devise and implement plans to conserve and maintain habitats and sites for Scottish invertebrates.Specific plans targeting the conservation of high

priority habitats and sites and also particular features of

importance will be prepared. In partnership with site

owners and managers, these plans will be implemented

and monitored. Habitat connectivity and the ability of

invertebrates to move in response to changes in their

environment will be key considerations.

OBJECTIVE 4

Prepare and disseminate general advice on managing habitats and sites for invertebrates.Information about the management of invertebrate

habitats will be collated. General advice on conserving

invertebrates in Scottish habitats and sites will be

prepared and disseminated. Demonstration sites will

be established and workshops will be held to promote

this advice.

Habitats and sites important for invertebrates need better

definition and recognition. Their management plans

need to incorporate requirements for key invertebrates;

and those declining habitats should be identified and

action taken to halt their loss. The following objectives are

designed to address these issues.

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Habitat and site conservation is sometimes not enough.

This is usually because some invertebrates have

requirements that are so specific they need targeted action.

In other cases species are so critically endangered that

tailored actions are the only answer. Species protected

by law also need individual conservation action and

management. With the right measures many species can

recover. Recent examples of recovery following protection

and establishment of new breeding sites are the New

Forest burnet moth (Zygaena viciae argyllensis) and the

Aspen hoverfly (Hammerschmidtia ferruginea).

An important part of this strategy is recognising and

actively conserving endangered Scottish invertebrates. To

determine the conservation status of invertebrates data are

needed on status, distribution and ecological requirements.

With thousands of species, difficult choices have to be

made and the starting point for this strategy is:

1. Species within existing initiatives - for example, the

UK Biodiversity Action Plan, Scottish Biodiversity

List and those protected by law - not yet under

active management (Appendices 4-6).

2. Species known or strongly suspected to be

endangered not covered under 1.

3. Species confined or mostly confined to Scotland.

4. Rare Scottish species i.e. species with a few

populations or records in Scotland but more

widespread elsewhere.

5. Reef building organisms and other keystone

marine invertebrates.

The Pine hoverfly (Blera fallax), is an endangered

hoverfly and confined to just two localities in

Inverness-shire. It breeds in holes and roots of live and

dead pine containing wet, decaying wood. Probably as a

result of the way pine woods have been managed in the

past, natural breeding sites are now very rare. The Pine

hoverfly was included in SNH’s Species Action Framework

and the Malloch Society is managing a project to

implement conservation measures to protect, maintain and

expand existing populations.

To overcome the lack of breeding sites, artificial ones

have been created by cutting holes in pine stumps and

by sinking plastic pots filled with pine wood chips and

saw dust into the ground. These have been successful

in attracting the Pine hoverfly to breed. Work is now

underway to find out how to make the artificial breeding

sites work in the best way. Data on water levels and

microbe populations in the breeding sites are being

studied to work out the conditions required for optimising

breeding success. It is hoped that the outcome of this

work, together with the management of pine woods in

a fashion that is sensitive to the requirements of the Pine

hoverfly, will ensure the survival of this original pioneer of

the Scottish landscape.

Species

CASE STUDY

Science improving management

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OBJECTIVE �

Produce and maintain a list of important Scottish invertebrates. Based on the categories above, data on Scottish

invertebrate species will be collected, collated, and

assessed in terms of status. Ecological requirements,

threats and gaps in knowledge will be identified.

OBJECTIVE 6

Devise and carry out a programme of prioritised invertebrate species assessment.An outline statement will be prepared for each

invertebrate group, detailing the current state of

knowledge and availability of data concerning

species status and requirements. A programme of

prioritised assessments will be developed to deal

with gaps in knowledge, including data deficient

species, and to address a lack of information on

species status and requirements.

OBJECTIVE 7

Devise and implement plans to conserve and maintain important Scottish invertebrates.Information about the requirements and needs of

prioritised invertebrate species will be collated and

made available to those who need it. In partnership

with site owners and managers, targeted plans will

be devised, implemented and monitored to conserve

and maintain these invertebrate species.

OBJECTIVE 8

Promote the study and recording of poorly recorded invertebrate groups.Poorly recorded groups of invertebrates will be

identified. Champions for these groups will be sought

and materials such as identification keys and advice will

be prepared to aid their study.

CASE STUDY

Promoting poorly recorded groups

Riverflies, defined here as mayflies (Ephemeroptera),

caddisflies (Trichoptera) and stoneflies (Plecoptera),

include 278 species in the UK. Following widespread

concern about a perceived decline in riverfly populations,

and the lack of data on these groups, The Riverfly

Partnership was established in �004 to increase our

knowledge of riverfly populations and to actively conserve

their habitats. The Partnership brings together anglers,

conservationists, entomologists, scientists, watercourse

managers and relevant authorities from across the UK.

Despite the importance of riverflies for monitoring river

water quality, there are few individuals studying these insects.

Much of the previous research into the decline of riverfly

populations was instigated by individuals and by voluntary

bodies. One of the key aims of the Riverfly Partnership is to

enable anglers to identify and record riverfly species.

To enable more people to study riverflies a series of easy

to use, inexpensive identification guides for caddisflies,

mayflies and stoneflies has been published by the

Partnership in collaboration with the Field Studies Council.

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Mobilising support for the Strategy

Existing data about Scottish invertebrates is scattered, of

variable quality and needs to be collated and mobilised.

Levels of awareness, participation and dissemination of

knowledge are poor. Advice on maintaining habitats, sites

and features important for invertebrates and conservation

plans for threatened species need to be promoted to

land owners and managers and potential funders for

implementation.

The objectives detailed below will help to address these

issues and push the management and conservation of

invertebrates higher up the environmental agenda.

OBJECTIVE 10

Provide the training and promotion necessary to implement this strategy.Training and promotion will be provided to meet

the needs of implementing the strategy. Partnership

agreements and regular communications will be

established between the ISI and all concerned with

implementing the strategy. The effectiveness of training,

communication and publicity will be monitored.

OBJECTIVE 11

Ensure the strategy is fully implemented into biodiversity, environmental and land use plans at national, regional and local levels.Invertebrate requirements and outputs from this

strategy will be communicated to the appropriate

bodies, organisations and individuals and incorporated

as appropriate into future plans, schemes and

legislation, such as agri-environment schemes and

development plans.

innovative apprenticeship scheme. Supported by

the Heritage Lottery Fund, Natural Talent offers paid

apprenticeships in vital taxonomic and specialist

conservation skills that are rapidly being lost from

the environmental sector.

Working primarily with environmental organisations

throughout Scotland and Northern Ireland, including

the Hunterian Museum, Ulster Museums and World

Museum Liverpool, apprentices gain “on the job”

experience and develop skills needed to begin to

specialise in their chosen field. BTCV Scotland is

currently coordinating apprenticeships in Coleoptera

and Hymenoptera, with apprentices in hoverflies and

micro-moths planned in the future. As the experts of

the future, Natural Talent apprentices will be involved in

implementing this strategy at all levels -from policy to

on the ground conservation and education.

OBJECTIVE 9

Devise and implement Scottish invertebrate data management protocols.Data management protocols and procedures will be

agreed and implemented in liaison with other relevant

organisations like the National Biodiversity Network

(NBN), national recording schemes and societies, Local

Record Centres, museums, statutory agencies and NGOs.

CASE STUDY

Building taxonomic capacity

The BTCV Natural Talent programme aims to train

the next generation of naturalists through an

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Appendix 1

Why invertebrates are important for the environment

An important service provided by invertebrates is

waste recycling - making minerals and organic material

available again to plants and other animals. In the soil,

earthworms and other invertebrates play crucial roles in the

decomposition of organic matter. Their activities improve

the drainage, aeration and composition of the soil, thus

enabling plant growth. The decomposition of dead plants

and animals including dung and fallen wood relies upon

invertebrates.

Most marine habitats are dominated by invertebrates. In

some cases, such as Flameshell (Limaria hians) reefs and

Northern sea fan (Swiftia pallida) and sponge communities,

the entire habitat is based on invertebrates. Birds and fish

rely on these invertebrates for food, and the abundance

and diversity of marine plankton is a useful indicator of

healthy marine ecosystems.

Many plants rely on insects to pollinate their flowers and so

complete their reproductive cycle. Well-known pollinators

include bumblebees, honeybees, butterflies and hoverflies;

less well-known ones include moths, thrips, beetles and

solitary bees.

Invertebrates form the basis of numerous food chains.

Many birds feed on invertebrates, whether as food for

their chicks or as part of their adult diet. Migrant birds

such as swallows, swifts and martins travel long distances

to feed on insects in the British Isles. The chicks of Blue

tits eat an estimated �� billion caterpillars and other small

invertebrates every year. A number of uplands birds, such

as Golden plovers and Greenshanks, time their breeding

to coincide with the emergence of craneflies, which form

the majority of the diet of their chicks. Baleen whales such

as the Minke whale and many seabirds feed extensively

on Krill (Euphausia superba) and other marine crustaceans.

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The diet of Puffins primarily consists of Sand eels, which in

turn feed upon planktonic species of crustacean and other

invertebrates. Mammals such as bats, badgers, voles and

shrews also feed on invertebrates. It is estimated that a

single Pipistrelle bat will consume over �,000 small insects

every night�. In freshwater ecosystems the diet of game

fish such as the Atlantic salmon and Brown/Sea trout is

comprised entirely of aquatic invertebrates. Birds such as

the Dipper and Grey wagtail also depend upon aquatic

invertebrates in our rivers and streams.

There is a long history of invertebrates being used as

indicators of the health of our environment. In determining

the quality of our rivers and lochs, the Scottish Environment

Protection Agency routinely use assessments of the

number and variety of aquatic invertebrates alongside

chemical analyses. Invertebrates are also used to test the

toxicity of chemicals such as pesticides.

Since 1979 the UK butterfly monitoring scheme has been

recording trends in butterfly species. The information

gathered plays an important role in assessing habitat

diversity, habitat fragmentation and the impacts of climate

and other environmental change. Through the Rothamsted

light-trap network, which started in 196�, we know that

about two-thirds of moth species are declining, and about

�0% of all species are declining sharply.

The Scottish Agricutural Science Agency monitors aphid

populations as part of the Rothamsted suction trap

network which has been in operation since 196�. The

information from this network is used to study the factors

affecting the dynamics of aphid populations and to guide

aphid control decisions.

In agricultural systems, simple measures such as conserving

headlands and making ‘beetle banks’ encourage predatory

invertebrates such as beetles and hoverflies, which not only

help to control pests but also provide additional food for

birds and mammals.

In addition, pests can be individually targeted with specific

invertebrate enemies like native ladybirds and parasitoid

wasps. Increasingly these are available commercially and

they may offer an environmentally friendly alternative to

chemical control.

3 Anon. (�00�). Pipistrelles. Species information leaflet. Bat Conservation Trust, London

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Appendix 2

Why invertebrates are important for the economy

The Scottish fishing industry relies on invertebrates

like shrimps, prawns, crabs, lobsters and other

shellfish such as mussels and oysters which make an

important contribution to the economy of coastal

communities. Catches of Langoustine (Norway Lobster or

Scampi) contribute £89.� million to the Scottish economy

each year – more than the combined catches of Cod,

Haddock and Monkfish4. In the pelagic fisheries our

important stocks of cod, herring and haddock depend on

invertebrates such as krill and copepods for their food.

Freshwater fisheries for game fish contribute over

£11� million annually to the Scottish economy�. Aquatic

invertebrates like stoneflies and mayflies are an essential

source of food for such fish.

Invertebrates provide a number of important ‘ecological

services’. These services are often overlooked until they are

damaged or lost. They are usually impossible to replace.

One example is crop pollination. Insects are responsible for

the pollination of a variety of crops in Scotland. The most

significant is the soft fruit industry, with the raspberry crop

in Scotland worth £�� million annually. The blackcurrant

crop is valued at £8 million; however, the associated

processing industry is worth an additional £�00 million6.

Invertebrates play an important role in sewage treatment.

One of the simplest but most effective treatments for

sewage involves passing the effluent over a bed of stones

on which a biofilm of bacteria, fungi and algae grow and

process the waste. The biofilm attracts, and is ingested

by, invertebrates including non-biting midges, moth-flies

and worms. Altogether these organisms turn the sewage

into clean water and an organic sludge that can be used as

fertiliser or fuel.

Earthworms and other soil invertebrates like springtails

benefit agriculture by maintaining and improving the

structure and aeration of soil by their constant feeding and

burrowing. They breakdown organic matter such as dead

leaves and return essential minerals and organic matter to

the soil so enabling renewed crop growth.

Tourism - especially ‘eco-tourism’ - constitutes an important

and increasing element of economic activity in Scotland.

Much of this is about history and landscape but it is also

about wildlife. Indirectly, invertebrates are important in

underpinning the survival of popular plants and animals

such as Ospreys and Otters. But there is also an increasing

interest in Scotland’s special invertebrate fauna. Certain

iconic species such as the Kentish glory moth (Endromis

versicolora), Chequered skipper (Carterocephalus palaemon)

and Mountain ringlet (Erebia epiphron) butterfly as well as

the many striking dragonflies, beetles and flies of our boreal

woodlands increasingly attract visitors not just from within

Scotland but also from other parts of the UK and Europe.

Some invertebrates have a negative economic impact.

For example certain aphids cause damage to crops, the

Heather beetle (Lochmaea suturalis) can affect areas of

moorland and the Pine looper moth (Bupalus piniarius) can

have an impact on Scots pine forests. In general however

these outbreaks are short lived and populations return

to a normal level within a season or two. A more difficult

issue is the biting midges (Culicoides species) which, at

high densities, can contribute to the loss of work-days and

potentially a loss of tourism revenue7.

4 Anon. (�007). Marine and Fisheries Business Plan �007/08. Department of Environment, Food and Rural Affairs.5 Radford, A., G. Riddington, J. Anderson, H. Gibson (�004). The Economic Impact of Game and Coarse Angling in Scotland. Research report prepared for Scottish Executive Environment and Rural Affairs Department.6 SCRI’s role in supporting the soft fruit industry. http://www.fruitgateway.co.uk/our_role.asp7 Blackwell, A., Ritchie, A., Hillman, J.R. and Fenton, B. (�00�). Meanbh-chuileag – The Highland biting midge. Scottish Crop Research Institute.

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CASE STUDY

Habitat loss

14

Appendix 3

Current threats and risks to Scottish invertebrates

In Scotland, as well as in other parts of Europe, there

is a general consensus that invertebrate abundance,

both in terms of overall population levels and

numbers of individual species, is declining. With large

numbers of species and an almost negligible amount

of systematic monitoring taking place it is difficult to be

definitive even within a comparatively well recorded area

such as the British Isles.

There is however information about some of the larger,

more charismatic groups which can be used to indicate

what may be happening to the fauna as a whole. Three of

the �� British species of bumblebees are now extinct in the

British Isles8, over 70% of butterfly species are in significant

decline and 66% of riverflies (caddisflies, mayflies and

stoneflies) have declined in recent years9. The abundance

of zooplankton in the seas around the United Kingdom has

declined by around 70% since 196010.

The loss and fragmentation of semi-natural habitats is a

major threat to invertebrate populations. This process

has been taking place for many generations, but it is now

taking a higher profile as development pressure increases

and the effects of climatic change make the continuity of

habitats to facilitate species movement a vital issue. This is

evidenced by recent data from the UK Butterfly Monitoring

Scheme. In Scotland, butterfly species that are largely

restricted to blocks of semi-natural habitat (‘specialists’)

are decreasing in abundance, whereas populations of

those species that can live in a broader range of habitats

(‘generalists’) are increasing11.

Natural habitats are under threat from a wide range of

activities. There is a need to take an overview of the

remaining natural habitats, and by planning and proactive

action ensure that habitat networks are maintained or

created. The use of invertebrates to identify critical

aspects such as patch size and dispersive corridors can be

in the forefront of achieving greater connectivity within our

natural habitats.

There is increasing pressure on habitats arising from

the need for more housing, industrial and recreational

The Mud snail (Omphiscola glabra) is typically

found in soft, nutrient poor waters with few other

aquatic animals or plants. These include freshwater

marshes, small ditches, temporary pools or seepages

that dry up or significantly diminish in summer.

These water-bodies are challenging habitats, which in the

past were regarded as inferior wildlife habitats and were

typically converted into productive agricultural land or

improved visually for landscape reasons. Historically, this

species was widespread throughout acidic lowland areas of

England, Wales and Scotland, as far north as Perth. A recent

survey has shown that this species has been lost from 64%

of historical sites in Scotland.

Loss and fragmentation of semi-natural habitats

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1�A strategy for Scottish invertebrate conservation

developments. In many cases the impact of these

developments on invertebrate species and populations is

unknown. Similarly, there is little information on whether

the mitigation measures proposed for invertebrates in

development plans actually work.

Overgrazing by Red deer and by sheep continues to

be an issue, both in the way in which it curtails natural

regeneration of woodland and scrub habitats but also in the

way that it decreases the structure and botanical diversity

of our upland areas. In lowland areas intensive farming

coupled with increased house building and development

pressure continues to be an issue and has led to a decrease

in the availability of suitable habitat for invertebrates.

In the marine environment many fragile ecosystems such

as Flameshell reefs and Northern sea fan and sponge

communities are prone to disturbance. Trawling for

langoustine and dredging for scallops can damage and

even completely destroy these fragile communities and the

invertebrates they contain.

Increased concentrations of nutrients in the environment

can have an adverse effect on habitats and their associated

invertebrates. Although diffuse pollution in the aquatic

environment is now being tackled through the use of

General Binding Rules for water managers, eutrophication

continues to be a serious problem in terrestrial ecosystems.

An increase in nutrients in the soil as a result of nitrogen

deposition or excessive use of fertilisers leads to changes in

the composition of the vegetation. Habitats such as bogs,

forests and unimproved grassland, and the invertebrates

they support, are all under threat from eutrophication.

8 Benton, T. (�006). Bumblebees. New Naturalist No. 98.9 Hayes, P. (�004). National River Fly Survey: headline results from the 19�0s to �001. Salmon and Trout Association, London.10 Anon. (�008). Marine Programme Plan �008/09. Department for Environment, Food and Rural Affairs, London. (http://www.defra.gov.uk/marine/pdf/mpp08-09.pdf)11 Anon. (�007). Scotland’s Biodiversity Indicators: S8 Terrestrial Insect Abundance: Butterflies. The Scottish Government, Edinburgh.12 Marine Conservation Society. http://www.mcsuk.org/mcsaction/fisheries/scallops

The Isle of Man fishery for Scallops began in

1937 with early catches consisting of large

numbers of large old scallops. The fishery

peaked in the mid 1980s with over 80 vessels

landing over 2,000 tonnes of scallops. By the

end of the 1980s the fishery had collapsed with

catches at an all time low and the majority of scallops

being below the legal catch size.

Areas of the seabed were closed to scallop dredging

in 1989 and with protection the number of scallops

steadily increased. There are now over 10 times as

many scallops in the protected areas compared to

the nearby fishing grounds and catch rates in the

fishing grounds have increased by 100%. The marine

communities in the protected areas have flourished

with the re-appearance of marine invertebrates such

as hydroids, sponges and fan-worms1�.

CASE STUDY

Habitat protection

Climatic change

Climate change is widely recognised as being one of

the major long term threats to biodiversity. Most recent

predictions are that Scotland will become warmer and

wetter as a result of climate change and this will inevitably

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The Australian barnacle (Elminius modesta) occurs

naturally in Australasia. It was introduced from

Australia or New Zealand either on the hull of a ship

or as larvae in ballast water. It was first recorded in

the British Isles in 194� and has since spread around our

coasts and was found as far north as Shetland in 198�. The

Australian barnacle competes with native species such as

the Acorn barnacle (Semibalanus balanoides). In addition,

the Australian barnacle can also tolerate lower salinity

habitats. The Bay barnacle (Balanus improvisus) which lives

in saline lagoons and other habitats with variable salinity

appears to be retreating where it is in competition with the

Australian barnacle1�.

Pollution

Whether on land, at sea, or in freshwaters, pollution

continues to be a serious problem for invertebrates, typically

leading to a decrease in the diversity and abundance of

invertebrate species. Freshwater invertebrates are affected

by various forms of pollution. Organic pollution can arise

from point sources such as sewage treatment works and

discharges from industry or as diffuse pollution such as

run-off from roads and buildings or fields. Acidification

continues to be a problem in some areas of Scotland and

various toxic chemicals can find their way into the aquatic

environment.

The use of chemicals such as pesticides can have

devastating effects on invertebrate populations. Sheep

dip compounds based on the synthetic pyrethroid

Cypermethrin pose a threat to both terrestrial and

freshwater invertebrates. Even a small amount of this

chemical dripping from a freshly dipped sheep can kill

aquatic invertebrates for many kilometres downstream.

Disposal of used sheep dip is typically by spraying it onto

CASE STUDY

Non-native species

have an impact on invertebrate populations. Indeed with

the majority of species having relatively short life cycles

and good powers of mobility they are likely to be one of

the first groups to show the impact of a changing climate.

Cold-loving species will retreat northwards and uphill, while

warm-loving species will increase their range and species

normally found further south in the UK and even in Europe

may become established in Scotland.

Temperature plays a vital role in the breeding success of

cold-blooded organisms and therefore the population size

and viability of many invertebrate species. It is probable

that small changes in temperature will be enough to

jeopardise the survival of some invertebrate populations.

This effect will most likely be seen in cold-adapted

montane species whose very survival may be at stake;

however, it is also evident in other habitats. In the marine

environment, the planktonic copepod Calanus finmarchius

(a cooler water species) has undergone a decline in

abundance while a warmer water species, Calanus

helgolandicus, has increased in abundance. The change in

the species composition of the marine plankton community

is evidence of a biological response to climate change1�.

Wetter conditions and an increase in the frequency of

summer floods are also likely to have a significant effect on

invertebrate populations. Ground-dwelling invertebrates

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may be drowned or washed away, and for those that

survive, the catastrophic loss of their food resource may

prove fatal.

17A strategy for Scottish invertebrate conservation

Non-native species

Many non-native species are now found in Scotland. An

audit by Scottish Natural Heritage in �001 found 988

non-native species of animal and plant occurring in

Scotland14. These species have arrived through a variety

of routes. Some have arrived accidentally, for example in

ballast water from ships, or alongside imported products

such as timber and fresh produce. Others have escaped

from gardens or were introduced as a food source.

Most non-native species pose no risk to our native wildlife,

and some are even beneficial; however, some species, if

conditions are conducive, can become invasive. Predation,

competition and the spread of disease from non-native

species are all potentially very harmful to our native wildlife.

The introduction of invasive non-native species to

semi-natural habitats can transform these habitats and

threaten the species that naturally live there.

Invasive non-native species can have serious negative

impacts on native species by predation, competition

and/or spread of disease. They transform habitats and can

13 Anon. (�007). Scotland’s Biodiversity Indicators: S14 Marine Plankton. The Scottish Government, Edinburgh.14 Welch, D., Carss, D.N., Gornall, J., Manchester, S.J., Marquiss, M., Preston, C.D., Telfer, M.G., Arnold, H., and Holbrook, J. (�001). An audit of alien species in Scotland. SNH Review No. 1�9. Scottish Natural Heritage, Edinburgh.15 Eno, N.C., Clark, R.A and Sanderson, W.G. (eds.). (1997). Non-native marine species in British waters: a review and directory. Joint Nature Conservation Committee, Peterborough.

Neglect and ignorance

Widespread views of invertebrates tend to emphasise their

negative aspects reinforcing the notion that ‘the only good

invertebrate is a dead one’ and that they do not matter.

Except for certain shellfish and pests, their environmental

and economic importance is little discussed or understood

outside narrow, special interest groups.

This is most evident in the marine environment where

invertebrates are often overlooked in favour of seabirds,

fish and cetaceans, despite many of these more popular

species depending upon invertebrates for their survival.

On both land and sea, the idea that invertebrates need

conservation as much as plants or vertebrates is not widely

accepted. They are neglected in assessments and

accorded a low priority amongst land owners, managers

and decision makers.

The majority of Scotland’s wildlife heritage comprises

invertebrates and if the threats to biodiversity are to be

properly addressed, then focussed attention on conserving

invertebrates will be essential.

threaten whole ecosystems, causing serious problems to

the environment and to the economy. In many cases this

may be exacerbated by the effects of climate change.

fields, potentially resulting in losses of invertebrates living

on, or under, the ground. The sale of Cypermethrin as

a sheep dip is currently banned, however its use is still

allowed and it can still be purchased for many other uses

including for the treatment of sea lice infestations in marine

fish farms, protection of crops, and for the control of fleas

and other invertebrates in the home. Avermectins, which

are used against intestinal worms and mites in livestock,

can have adverse effects on dung fauna and soil-dwelling

invertebrates.

In the marine environment, the effects of pollution are less

obvious, however they are still as damaging. Anti-fouling

paints were developed in the 1960s to prevent the build

up of barnacles and other organisms on the hulls of ships.

Whilst these paints were designed to target particular

species, they have since been found to cause sex-reversal

in non-target molluscs, leading to near extinction of some

species in some areas. The use of these paints will be

completely phased out by the end of �008, however their

legacy will continue as the constituent chemicals persist in

the sediment.

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Appendix 4

Scottish Biodiversity List species and UKBAP Priority Species that occur in Scotland

Order Common Name UKBAP16 SBL17

Annelida Worms, leeches, etc. - 1

Araneae Spiders 10 8

Bryozoan Moss animals - 13

Cnidaria Sea anemones, Jellyfish, Sea pens, etc. 8 15

Coleoptera Beetles 10 82

Crustacea Crustaceans 5 2

Dermaptera Earwigs - 1

Diptera True-flies 12 62

Echinodermata Sea stars - 1

Ephemeroptera Mayflies 1 -

Hemiptera True-bugs - 4

Hymenoptera Bees, wasps and ants 11 63

Lepidoptera Butterflies and moths 95 35

Mollusca Snails and slugs 10 39

Nemertinea Ribbon worms - 11

Neuroptera Lacewings 1 2

Odonata Dragonflies and damselflies - 1

Orthoptera Grasshoppers, crickets, etc. - 2

Plecoptera Stoneflies 1 1

Porifera Sponges - 8

Siphonaptera Fleas - 1

Trichoptera Caddisflies 1 -

Tunicata Sea squirts 1 -

Total 166 350

Appendix 5

Internationally protected species that occur in Scotland

Scientific name Common name EC Annex18 Bern Appendix19 CITES Appendix20

Lepidoptera (butterflies)

Euphydryas aurinia Marsh fritillary butterfly IIa II -

Crustacea (crayfish and shrimps)

Austropotamobius pallipes White-clawed crayfish IIa, Va III -

Mollusca (bivalves, snails and slugs)

Margaritifera margaritifera Pearl mussel IIa, Va III -

Vertigo angustior Narrow-mouthed whorl snail IIa - -

Vertigo genesii Round-mouthed whorl snail IIa - -

Vertigo geyeri Geyer’s whorl snail IIa - -

Annelida (segmented worms)

Hirudo medicinalis Medicinal leech Va III II

18 Directive 9�/4�/EEC on the Conservation of Natural Habitats and of Wild Fauna and Flora (Habitats Directive)l Annex IIa - designation of protected areas for animal species listedl Annex Va - exploitation of listed animal species to be subject to management if necessary

19 Council of Europe Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention)l Appendix II - special protection for listed animal species and their habitatsl Appendix III - exploitation of listed animal species to be subject to regulation

�0 Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)lAppendix I - trade only in exceptional circumstances for species listedl Appendix II - trade in listed species subject to licensingl Appendix III - trade in listed species subject to limited licensing

CITES regulations apply also to other non-native species not listed here.

16 Number of UKBAP Priority Species that occur in Scotland. A full list of UKBAP Priority Species can be found at www.ukbap.org.uk17 Scottish Biodiversity List species. A full list of Scottish Biodiversity List species can be found at www.biodiversityscotland.gov.uk

19A strategy for Scottish invertebrate conservation

Scientific name Common name Sections of Act in force Year scheduled

Lepidoptera (butterflies)

Aricia artaxerxes Northern brown argus Sale only S. 9(5) 1989

Boloria euphrosyne Pearl-bordered fritillary Sale only S. 9(5) 1989

Carterocephalus palaemon Chequered skipper Sale only S. 9(5) 1989

Coenonympha tullia Large heath Sale only S. 9(5) 1989

Cupido minimus Small blue Sale only S. 9(5) 1989

Erebia epiphron Mountain ringlet Sale only S. 9(5) 1989

Euphydryas aurinia Marsh fritillary Full protection 1998

Lepidoptera (moths)

Zygaena viciae New Forest burnet Full protection 1981

Crustacea (crayfish and shrimps)

Austropotamobius pallipes White-clawed crayfish Taking S. 9(1) (part). Sale S. 9(5)

1988

Triops cancriformis Tadpole shrimp Full protection 1988

Mollusca (bivalves, snails and slugs)

Atrina fragilis Fan mussel Killing, injuring & taking S. 9(1)Possession S. 9(2) Sale S 9(5)

1998

Margaritifera margaritifera Freshwater pearl mussel Full protection 1998

Paludinella littorina Lagoon snail Full protection 1992

Tenellia adspersa Lagoon sea slug Full protection 1992

Thyasira gouldi Northern hatchet-shell Full protection 1992

Annelida (segmented worms)

Hirudo medicinalis Medicinal leech Full protection 1988

Appendix 6

Species known from Scotland that are protected by the Wildlife and Countryside Act 1981

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The development and publication of this strategy has been supported by the following organisations:

Buglife – The Invertebrate Conservation Trust is convinced that the implementation of this strategy will secure the future of Scotland’s invertebrate fauna and the associated benefits. We are delighted that the strategy has such universal support and look forward to working in partnership to provide a bright future for bugs.

The Bumblebee Conservation Trust are delighted to support this new initiative that seeks to unite invertebrate conservation efforts in Scotland, and hope that it will succeed in raising the profile of this often-overlooked group of organisms that comprise the majority of species on Earth.

This strategy is endorsed and commended by Butterfly Conservation. It emphasises the essential role of invertebrates within Scotland’s ecosystems, and the need for nature conservation to give due regard to the myriad species that live around us. As such, it is a valuable step on the long road to safeguarding all of our biodiversity for future generations to enjoy, utilise and of which to be proud.

Forestry Commission Scotland are pleased to support the publication of an invertebrate conservation strategy for Scotland and look forward to playing a part in implementing it in Scottish woodlands.

The Initiative for Scottish Invertebrates is grateful to all the organisations and individuals who have supported and helped in the development of this strategy. It represents a crucial milestone for Scottish invertebrates, however the amount of work before us is daunting and we need the continuing support and active participation of many individuals and organisations to achieve results. With the launch of the strategy we have before us an historic opportunity to show what can be done not only for Scotland and the rest of the UK, but for Europe and the rest of the world too.

The John Muir Trust strongly supports this strategy. We strive to deliver for biodiversity, including invertebrates, on wild land.

RSPB Scotland supports this strategy and has been pleased to contribute to its development. We hope it will complement both the partnership effort to advocate beneficial policies and practice across Scotland, and our direct management work for invertebrate species on RSPB nature reserves.

The Scottish Wildlife Trust is pleased to support the development and implementation of this strategy which is an important milestone in the conservation of invertebrates in Scotland.

SNH has supported the development of this strategy by the Initiative for Scottish Invertebrates because we recognise the crucial importance of voluntary enthusiasts to the conservation of this huge and difficult group of organisms. As the strategy emphasises, most animals in Scotland are invertebrates and they underpin the functioning of every element of our landscape, and the sea. The implementation of this strategy will be a long and difficult road for invertebrate supporters but one that should bring a great sense of achievement and SNH will work with you on every inch of the journey.

SEPA is pleased to support the development and implementation of this strategy. Beyond their biodiversity value, invertebrates are key indicators of environmental health and play an important role in environmental monitoring. Increasing knowledge of Scottish invertebrates will enable SEPA to carry out its regulatory activities in a manner that will minimise its impact on priority species.

ISIInitiative for

Scottish Invertebrates